A metal having a smaller particle diameter is known to exhibit specific physical characteristics. Particularly, nano-scale particles significantly exhibit such a tendency. Attempts have been made to use, for example, metal nanoparticles as a bonding material between different substances by utilizing a property in which the melting point thereof is particularly lower than that of a bulk body.
The present applicant also has developed a paste for bonding (bonding material) containing silver nanoparticles and disclosed it in Patent Literatures 1 and 2. In addition, attempts have been made to use silver nanoparticles as a metal material for bonding. For example, techniques in Patent Literatures 3 and 4 are exemplified.